1. Field of the Invention
The present invention relates to a tilting structure for tilting a backrest of a seat backward until the backrest and a seat cushion of the seat are substantially aligned with each other.
2. Description of the Related Art
Recreational vehicles (RVs) dedicated for enjoying leisure activities are finding widespread use among people whose life-styles are changing in recent years. It is known that when the backrest of a seat in such recreational vehicles is tilted backward and the rear end of the seat cushion is tilted upward, the backrest and the seat cushion are substantially aligned with each other.
Japanese utility model publication No. 64-6346 discloses a lifter device comprising a first rod angularly movably mounted on a side plate of a cushion frame of a seat cushion, and a second rod angularly movably mounted on a base and angularly movably coupled to the first rod. When a back frame of a backrest is tilted backward, the first and second rods are angularly moved through a moving mechanism, causing the rear end of the seat cushion to be lifted until the seat cushion and the backrest are substantially aligned with each other.
The lifter device is directly mounted on the cushion frame of the seat cushion. Therefore, the lifter device cannot be used in combination with a seat structure which allows the rear surface of a backrest to be used as a cargo base when a seat cushion is lifted forward and the backrest is lowered or tilted down forward toward the seat cushion. Consequently, the lifter device is not versatile in applications, and may not be used with seats in recreational vehicles, for example.
FIG. 20 of the accompanying drawings shows known rear seats 2a, 2b in a recreational vehicle, each having a backrest that can be tilted a large angle rearward. The rear seats 2a, 2b have respective seat cushions 3a, 3b and respective backrests 4a, 4b. When the backrests 4a, 4b are tilted rearward, the rear seats 2a, 2b are made substantially flat.
The recreational vehicle has wheel houses 5a, 5b which accommodate rear wheels and rear suspension damper bases. Since the wheel houses 5a, 5b are positioned behind the rear seats 2a, 2b, respectively, they prevent the backrests 4a, 4b from being tilted rearward in their entirety. Usually, when the backrests 4a, 4b are tilted rearward, side portions 6a, 6b of the respective backrests 4a, 4b remain untilted due to physical interference with the wheel houses 5a, 5b. AS a result, the width H, i.e., the dimension in the transverse direction of the motor vehicle, of those portions of the backrests 4a, 4b which can be tilted rearward is considerably small.